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In this chapter you will learn about the following: Describe the basic structure of the legal system in the United States, relate how laws affect the paramedic’s practice, list situations that a paramedic is legally required to report in most states, describe the four elements involved in a claim of negligence, describe measures paramedics may take to protect themselves from claims of negligence.
9/11/2012 Chapter 46 Obstetrics Learning Objectives • Describe the basic anatomy and physiology of the female reproductive system • Outline fetal development from ovulation through birth • Explain normal maternal physiological changes that occur during pregnancy and how they influence prehospital patient care and transportation Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 9/11/2012 Learning Objectives • Describe appropriate information to be elicited during the obstetrical patient’s history • Describe specific techniques for assessment of the pregnant patient • Describe the general prehospital care of the pregnant patient • Discuss the special implications of trauma in pregnancy Learning Objectives • Outline principles of care for a pregnant patient in cardiac arrest or peri‐arrest • Recognize and begin treatment for complications of pregnancy such as hyperemesis gravidarum, Rh sensitization, diabetes mellitus, and infection • Describe the assessment and management of patients with preeclampsia and eclampsia Learning Objectives • Explain the pathophysiology, signs and symptoms, and management of vaginal bleeding in pregnancy • Outlinethephysiologicalchangesthatoccur duringthestagesoflabor Describetheroleoftheparamedicduring normallaboranddelivery Copyright â 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 9/11/2012 Learning Objectives • Compute an Apgar score • Describe assessment and management of postpartum hemorrhage • Discuss the identification, implications, and prehospital management of complicated deliveries Female Reproductive Anatomy • Comprised of external and internal anatomic structures – Allow for pregnancy • External genitalia – Labium minora – Labium majora – Vagina – Clitoris Female Reproductive Anatomy • Internal organs; lie within pelvis – Uterus – Ovaries – Uterine (or fallopian) tubes – Cervix Undercontrolofendocrinesystemand hormones Copyright â 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 9/11/2012 Female Reproductive Anatomy • For women of childbearing age – Cycle usually a monthly event • Begins with menstruation (shedding of the endometrium or uterine lining) • Ends with pregnancy OR • Absence of fertilization, another menstrual cycle 10 11 Normal Events in Pregnancy • Fertilization normally occurs in fallopian tube – Head of sperm penetrates mature ovum – Nuclei of sperm and ovum fuse – Newly fertilized ovum becomes zygote – Zygote undergoes repeated cell divisions as it passes down tube 12 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 9/11/2012 Normal Events in Pregnancy • Fertilization normally occurs in fallopian tube – After few days of cell division, ball of cells called morula formed • Cell differentiation between inner layer cells (blastocyst cells) and outer layer cells (trophoblast cells) – Trophoblast cells attach to endometrium lining of uterus – Implantation begins within 7 days after fertilization • Completed when trophoblast make contact with maternal circulation • About day 12 13 Normal Events in Pregnancy • Fertilization normally occurs in fallopian tube – Trophoblast go on to make various life support systems for embryo • Placenta • Amniotic sac • Umbilical cord – Blastocyst cells develop into embryo itself 14 15 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 9/11/2012 Specialized Structures of Pregnancy • Provide nutrients for developing embryo • Part of fetal circulation – Placenta – Umbilical cord – Amniotic sac and its fluid 16 Placenta • Disk‐like organ composed of interlocking fetal and maternal tissues • Trophoblast cells continue to develop and form placenta for about 14 days after ovulation • Organ of exchange between mother and fetus 17 Placenta • Responsible for five functions – Transfer of gases • Diffusion of oxygen and carbon dioxide through placental membrane (similar to diffusion that occurs in lungs) • Dissolved oxygen in maternal blood passes through placenta into fetal blood • Takes place as result of increase in partial pressure of oxygen in mother’s blood compared to fetus • Fetal carbon dioxide pressure (Pco2) accumulates, a low pressuregradientofcarbondioxidedevelopsacross placentalmembrane Carbondioxidediffusesfromfetalbloodtomaternalblood 18 Copyright â 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 9/11/2012 Placenta • Responsible for five functions – Transport of nutrients • Other metabolic substrates that fetus needs diffuse into blood in same manner as oxygen • Glucose in fetal blood about 20 to 30 percent lower than maternal blood • Results in rapid diffusion of glucose to fetus • Transports other substrates; fatty acids, potassium, sodium, and chloride • Actively absorbs some nutrients from maternal blood 19 Placenta • Responsible for five functions – Excretion of wastes • • • • Diffuse from fetal blood into maternal blood Examples are urea, uric acid, and creatinine Excreted with waste products of mother Transfer from fetal circulation to maternal circulation moving osmotically from higher concentration to lower concentration; same manner as carbon dioxide 20 Placenta • Responsible for five functions – Hormone production • Placenta becomes temporary endocrine gland • Secretes estrogen and progesterone • By third month of development, corpus luteum on the ovary no longer is needed to sustain pregnancy • Estrogen,progesterone,andotherhormonesmaintain uterinelining,preventoccurrenceofmenses Stimulatechangesinpregnantwoman'sbreasts, vagina,cervix,andpelvis 21 Copyright â 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 9/11/2012 Placenta • Responsible for five functions – Formation of barrier • Placenta forms barrier against some harmful substances in mother's circulation (e.g., bacteria and certain drugs) • Only partially selective and does not fully protect fetus • Certain medications easily cross placenta – – – – Steroids Narcotics Anesthetics Some antibiotics 22 What happens to diffusion of gases if the mother becomes hypoxic? 23 Fetal Circulation • Umbilical cord connects umbilicus with placenta • The average umbilical cord is about 55 cm long with diameter of 1 to 2 cm 24 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 9/11/2012 Fetal Circulation • Blood flows from fetus to placenta through two umbilical arteries in cord – Arteries carry deoxygenated blood – Oxygenated blood returns to fetus through umbilical vein • Independent of and separated from maternal circulation 25 Fetal Circulation • Anatomic structures unique to fetal circulation – Ductus venosus • Continuation of umbilical cord • Serves as shunt to allow most blood returning from placenta to bypass immature liver • Allows blood to empty directly into inferior vena cava • Allow blood to bypass embryo’s lungs • Lungs remain collapsed until birth – Foramen ovale • Shunt from right atrium into left 26 Fetal Circulation • Anatomic structures unique to fetal circulation – Ductus arteriosus • Connects pulmonary artery to aorta • Well‐oxygenated blood from placenta enters left side of heart directly from right side, bypassing lungs • Left ventricle pumps oxygenated blood mainly into vessels of head and forelimbs • Blood entering right atrium from superior vena cava progresses downward through tricuspid valve into right ventricle 27 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 9/11/2012 Fetal Circulation • Anatomic structures unique to fetal circulation – Ductus arteriosus • Most of this blood is deoxygenated blood from head of fetus • Blood is pumped by right ventricle into pulmonary artery • Deoxygenated blood passes from pulmonary artery, through ductus arteriosus, into descending aorta, through two umbilical arteries, and into placenta for oxygenation • At birth, various arteriovenous shunts close in most infants 28 29 Amniotic Sac and Fluid • Completely surrounds embryo • Contains fluid primarily produced by fetal urine and placenta • Fluid is continually produced 30 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 10 9/11/2012 Delivery Procedure • First‐twin delivery is identical to single delivery with same presentation – Up to 50 percent of second‐twin deliveries are not in normal presentation position – Fetuses are smaller in multiple births 283 Delivery Procedure • After delivery of first twin, cut and clamp (or tie) umbilical cord as described earlier – Within 5 to 10 minutes after delivery of first twin, labor begins again – Delivery of second twin usually occurs within 30 to 45 minutes – Medical direction may recommend transport before delivery of second twin – Usually both twins are born before delivery of placenta 284 Delivery Procedure • Infants in multiple births often are smaller than infants in single term births – Give special attention to keeping these infants warm, well oxygenated, and free from unnecessary contamination as described for premature infants 285 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 95 9/11/2012 Delivery Procedure • Postpartum hemorrhage may be more severe after multiple births – Hemorrhage may require • Fluid resuscitation • Uterine massage • Oxytocin infusion to control bleeding 286 Precipitous Delivery • Rapid spontaneous delivery with less than 3 hours from onset of labor to birth – Results from overactive uterine contractions and little maternal soft tissue or bony resistance – Most often occurs in mother who is grand multipara 287 Precipitous Delivery • Can be associated with soft tissue injury and uterine rupture (rare) – Has increased perinatal mortality rate because of trauma and hypoxia – Main danger to fetus is from cerebral trauma or tearing of umbilical cord 288 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 96 9/11/2012 Precipitous Delivery • If paramedic expects a precipitous delivery, attempts should be made to prevent explosive one – Can be done by providing gentle counterpressure to infant’s head • Do not attempt to detain fetal head descent • After delivery, infant should be kept dry and warm to prevent heat loss • Mother should be examined for perineal tears that often accompany rapid birth 289 Uterine Inversion • Infrequent complication of childbirth where uterus turns “inside out” – Thought to occur in about 1 in 2000 deliveries – Serious condition – Resultant postpartum hemorrhage is associated with maternal mortality rate of around 15 percent 290 Uterine Inversion • May occur suddenly after contraction or with increased abdominal pressure caused by coughing or sneezing – More often is caused by medical personnel or medical procedure (iatrogenic), secondary to excessive pulling on umbilical cord and fundal massage 291 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 97 9/11/2012 Uterine Inversion • Risk is higher when placenta has implanted high in uterus – Incomplete if uterine fundus does not extend beyond cervix – Complete if fundus does protrude through cervix – Prolapsed if entire uterus protrudes through vaginal ring 292 Uterine Inversion • Signs and symptoms of uterine inversion include postpartum hemorrhage and sudden and severe lower abdominal pain – Hemorrhage may be profuse – Hypovolemic shock may develop quickly 293 Management • Prehospital care – Airway, ventilatory, and circulatory support – Rapid transportation for physician evaluation – Medical direction may recommend that paramedic attempt manual replacement of uterus only if cervix has not yet constricted 294 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 98 9/11/2012 Management • Technique for manual replacement is as follows – Place patient in supine position – Do not attempt to remove placenta if it has not already been delivered • Doing so is likely to increase hemorrhage – Apply pressure with fingertips and palm of gloved hand and push fundus upward and through cervical canal • If this is ineffective, cover all protruding tissues with moist sterile dressings and rapidly transport patient 295 Management • Manual replacement of uterus may be painful to patient – Medical direction may indicate use of analgesics – Paramedic should explain need for procedure to patient 296 Pulmonary Embolism • Development of pulmonary embolism during pregnancy, labor, or postpartum period is significant cause of maternal death – Embolus often results from blood clot in pelvic circulation (venous thromboembolism) – Slight increased risk of pulmonary embolus with cesarean versus vaginal delivery 297 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 99 9/11/2012 Pulmonary Embolism • Patient often has classic signs and symptoms – – – – – Sudden dyspnea Sharp, focal chest pains Tachycardia Tachypnea Sometimes hypotension • Prehospital care – Airway, ventilatory, and circulatory support – ECG monitoring – Rapid transportation for physician evaluation 298 Premature Rupture of Membranes • Rupture of amniotic sac before onset of labor – Termed premature regardless of fetal age – Occurs in about 3 percent of pregnancies – In 10 to 15 percent of all cases, fetus is at or near term 299 Premature Rupture of Membranes • Signs and symptom include history of trickle or sudden gush of fluid from the vagina – Transport patients for physician evaluation – Medical facility will prepare for delivery if patient begins labor – Delivery is required if infection of fetal membranes is diagnosed (chorioamnionitis) 300 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 100 9/11/2012 Premature Rupture of Membranes • Chorioamnionitis is linked to premature rupture of membranes occurring 24 hours before labor begins – Can occur with prolonged labor, in part due to multiple vaginal exams – Infection generally is accompanied by maternal fever, chills, and uterine pain – Infection is treated with antibiotics – Definitive treatment is delivery of fetus 301 Amniotic Fluid Embolism • When amniotic fluid enters maternal circulation during labor or delivery or immediately after delivery, amniotic fluid embolism can occur – Probable routes of entry • Lacerations of endocervical veins during cervical dilation • Lower uterine segment or placental site • Uterine veins at sites of uterine trauma 302 Amniotic Fluid Embolism • Particulate matter in amniotic fluid (e.g., meconium, lanugo hairs, and fetal squamous cells) forms an embolus and obstruct pulmonary vasculature – Amniotic fluid embolism is rare, occurring in 6 to 14.8 per 100,000 primigravid and multiparous deliveries, respectively 303 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 101 9/11/2012 Amniotic Fluid Embolism • Most often seen in multiparous women late in first stage of labor – Other conditions that can increase incidence • Placenta previa • Abruptio placentae • Intrauterine fetal death – Maternal mortality rate high 304 Amniotic Fluid Embolism • Signs and symptoms of amniotic fluid embolism are same as those for pulmonary embolism – May include cardiopulmonary arrest • Treatment – Airway, ventilatory, and circulatory support – Fluid resuscitation – Rapid transportation 305 Summary • Cultural differences may influence a woman’s response to pregnancy and childbirth – Paramedic should be sensitive to these cultural beliefs • Fertilization of an ovum by a sperm forms a zygote that divides as it passes through fallopian tube to become a morula – Trophoblast cells of the morula implant within 7 days after fertilization and transform into the life support systems of the embryo – Blastocyst cells develop into the embryo 306 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 102 9/11/2012 Summary • Placenta is a disklike organ – Composed of interlocking fetal and maternal tissues – Organ of exchange between mother and fetus – Blood flows from fetus to placenta through two umbilical arteries • Carry deoxygenated blood – Oxygenated blood returns to fetus through umbilical vein – Amniotic sac is a fluid‐filled bag that completely surrounds and protects embryo 307 Summary • Developing ovum is known as an embryo during first 8 weeks of pregnancy – After that time and until birth it is called a fetus – Gestation (fetal development) usually averages 40 weeks from time of fertilization to delivery of newborn • At birth, in normal newborn, the atriovenous shunts present in fetus close 308 Summary • Gravida is total number of current and past pregnancies – Para refers to past pregnancies that resulted in a live birth • Pregnant woman undergoes many physiological changes that affect the genital tract, breasts, gastrointestinal system, cardiovascular system, respiratory system, and metabolism 309 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 103 9/11/2012 Summary • Patient history should include obstetrical history; presence of pain; presence, quantity, and character of vaginal bleeding; presence of abnormal vaginal discharge; presence of “bloody show”; current general health and prenatal care; allergies and medicines taken; and maternal urge to bear down 310 Summary • Goal in examining an obstetrical patient is to rapidly identify acute life‐threatening conditions – Part of this involves recognizing imminent delivery – Then paramedic must take the proper management steps • In addition to the routine physical examination, the paramedic should assess the abdomen, uterine size, and fetal heart sounds 311 Summary • If birth is not imminent, paramedic should limit prehospital care for healthy patient – Limited to basic treatment modalities – Includetransportforphysicianevaluation Causesoffetaldeathfrommaternaltrauma includedeathofmother,separationofthe placenta,maternalshock,uterinerupture,and fetalheadinjury 312 Copyright â 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 104 9/11/2012 Summary • To treat a critically ill pregnant patient, administer high‐concentration oxygen – Tilt patient left lateral – Administer IV fluid if there are signs of shock – Aggressively resuscitate mother in an attempt to save baby – Cardiac arrest can occur from a number of causes – Rapid transport is indicated 313 Summary • Hyperemesis gravidarum presents with severe nausea, vomiting, weight loss, and electrolyte disturbance – Fluid therapy is indicated if there are signs of dehydration • Rh sensitization occurs if the mother has Rh‐ negative blood and the baby Rh‐positive blood – It can cause anemia, jaundice, edema, enlarged liver or spleen, and hydrops 314 Summary • Gestational hypertension is onset of BP over 140/90 mmHg during pregnancy – Can indicate preeclampsia • Preeclampsia occurs after 20 weeks gestation – Criteria for diagnosis include hypertension, protein in the urine, and excessive weight gain with edema – Eclampsia is characterized by the same signs and symptoms with addition of seizures or coma 315 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 105 9/11/2012 Summary • Gestational diabetes mellitus is diabetes caused by pregnancy • Infection during pregnancy can place the mother and fetus at risk – TORCH is an acronym for infections mother can pass to fetus that cause fetal death or complication 316 Summary • Vaginal bleeding during pregnancy can result from abortion (miscarriage), ectopic pregnancy, abruptio placentae, placenta previa, uterine rupture, or postpartum hemorrhage – Abortion is termination of pregnancy from any cause before 20 weeks gestation – Ectopic pregnancy occurs when a fertilized ovum implants anywhere other than the uterus – Abruptio placentae is partial or complete detachment of the placenta at more than 20 weeks gestation 317 Summary • Placentaprevia isplacentalimplantationin theloweruterinesegmentpartiallyor completelycoveringthecervicalopening Uterineruptureisaspontaneousortraumatic ruptureoftheuterinewall 318 Copyright â 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 106 9/11/2012 Summary • First stage of labor begins with the onset of regular contractions – Ends with complete dilation of the cervix • Second stage of labor is measured from full dilation of the cervix to delivery of infant • Third stage of labor begins with delivery of infant and ends when placenta is expelled and uterus has contracted 319 Summary • One of the primary responsibilities of the EMS crew is to prevent an uncontrolled delivery – Other is to protect infant from cold and stress after birth • Criteria for computing Apgar score include appearance (color), pulse (heart rate), grimace (reflex irritability), activity (muscle tone), and respiratory effort 320 Summary • More than 500 mL of blood loss after delivery of newborn is called postpartum hemorrhage – Often results from ineffective or incomplete contraction of the uterus • Paramedics should be alert to factors that point to a possible abnormal delivery 321 Copyright © 2013 by Jones & Bartlett Learning, LLC, an Ascend Learning Company 107 9/11/2012 Summary • Cephalopelvic disproportion produces a difficult labor because of presence of a small pelvis, an oversized uterus, or fetal abnormalities – Most infants are born head first (cephalic or vertex presentation) 322 Summary • Sometimes presentation is abnormal – In breech presentation, largest part of fetus (head) is delivered last – Shoulder dystocia occurs when the fetal shoulders impact against maternal symphysis pubis, which blocks shoulder delivery • Shoulder presentation (transverse presentation) results when long axis of fetus lies perpendicular to that of mother • Fetal arm or hand may be presenting part • Cord presentation occurs when cord slips down into vagina or presents externally 323 Summary • Premature infant is born before 37 weeks gestation • Multiple gestation is a pregnancy with 1+ fetus and is accompanied by an increased complication rate • Precipitous delivery is rapid spontaneous delivery with